import java.util.Scanner;

public class demo05 {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        System.out.println("请输入学生成绩：");
        double a = scanner.nextDouble();
        if (a<=0||a>100){
            System.out.println("成绩输入有误，请重新输入");
        }
        else if(a<60){
            System.out.println("学生等级为：C");
        }else if (a<=80){

        }else {
            System.out.println("学生等级为：A");
        }
    }
}
